import fs from 'fs';
fs.writeFile('./bbb.txt','hello world',{
    encoding:'utf-8',
    flag:'a+'
},(err)=>{
    console.log('写入文件结果：',err);
});

const writeStream = fs.createWriteStream('./ccc.txt',{
    flags:'a'
});

writeStream.on('open',(fd)=>{
    console.log('文件被打开',fd);
});

writeStream.write('coderwhy');
writeStream.write('aaaa');
writeStream.write('bbbb',(err)=>{
    console.log("写入完成:",err);
});

writeStream.on('finish',()=>{
    console.log('写入完成');
});

writeStream.on('close',()=>{
    console.log('文件被关闭');
});
writeStream.end('哈哈哈哈');